Vehicles of recent interest as environmentally-friendly vehicles are those equipped with a power storage device (such as secondary battery or capacitor for example) and caused to travel by a drive force that is generated by a motor using electric power stored in the power storage device. Such vehicles include for example electric vehicles, hybrid vehicles, fuel cell vehicles, and the like.
In these vehicles, electric power conversion devices such as converter and inverter may be used for driving the motor. In some cases, it may become necessary to restrict the output of the motor for the sake of parts protection, based on the temperature characteristics of these power conversion devices and the temperature characteristics of the power storage device.
Japanese Patent Laying-Open No. 2006-149064 (PTL 1) discloses a configuration of a vehicle drive system driven by an inverter. Specifically, a torque command value for a rotating electric machine is restricted in the case where the temperature of a coolant for cooling the inverter is close to the temperature of the inverter. The vehicle drive system disclosed in Japanese Patent Laying-Open No. 2006-149064 (PTL 1) can provide a vehicle having improved compatibility of system protection at high temperatures with power performance or fuel efficiency.